Consumption of dark chocolate could help to shrink the risk of heart disease in people with metabolic syndrome, according to new scientific data.

The research – published in the British Medical Journal – assessed the long term value, and cost effectiveness, of daily dark chocolate consumption in a population with metabolic syndrome at high risk of cardiovascular disease.

Led by Professor Christopher Reid, from Monash University, Australia, the research team used mathematical models to predict the long-term health effects and cost effectiveness of daily dark chocolate consumption in 2,013 people already at high risk of heart disease.

The Australian researchers revealed that daily consumption of flavonoid-rich dark chocolate could slash the risk of cardiovascular events, such as heart attacks and strokes, in people with metabolic syndrome.

The team revealed that consumption could potentially avert 70 non-fatal and 15 fatal cardiovascular events per 10,000 people over 10 years – leading them to conclude that the blood pressure and cholesterol lowering effects of plain dark chocolate "could represent an effective and cost effective strategy for people with metabolic syndrome (and no diabetes)."

“Daily dark chocolate consumption could be an effective cardiovascular preventive strategy in this population,” they noted.

“Evidence to date suggests that the chocolate would need to be dark and of at least 60-70% cocoa, or formulated to be enriched with polyphenols.”

Chocolate benefits

Dark chocolate (containing at least 60% cocoa solids) is rich in flavonoids are known to have beneficial effects for the heart – however the researchers noted that such benefits have only ever been examined in short term studies.

Previous research has suggested that dark chocolate has benefits for blood pressure, inflammation, blood clotting, and could also have metabolic effects. Such short term trials have, for example, shown that dark chocolate consumption can potentially reduce systolic blood pressure by 5 mm Hg and lower total cholesterol concentration by 0.21 mmol/L.

Study details

The population used in the model comprised participants selected from the Australian Diabetes Obesity and Lifestyle (AusDiab) study, among whom cardiovascular risk was estimated individually.

All participants had high blood pressure and met the criteria for metabolic syndrome, but had no history of heart disease or diabetes and were not on blood pressure lowering therapy.

Even when compliance levels were reduced to 80%, Reid and his team revealed that the number of non-fatal and fatal events potentially averted was 55 and 10 per 10,000 people treated over 10 years – therefore meaning consumption could still be considered an effective intervention strategy.

The model also suggested that €31 ($42USD) could be cost effectively spent per person per year on dark chocolate prevention strategies and could be used for advertising, educational campaigns, or subsidising dark chocolate in this high risk population, said the research team.

However, they stressed that only non-fatal stroke and non-fatal heart attack have so far been assessed using the model – noting that the potential effects on other cardiovascular events, such as heart failure, are yet to be tested.